Cobalt-containing azo dyestuffs of the



2,820,782= COBALT-CONTADIING AZO DYESTUFFS F ACYLACETYLAMINOALKANE SERIES Piero Maderni; Basel, and WalterWehrli, Riehen, Switzerland, assignors to Saul & Co., Newark, N. J., as

Nominee of Fidelity Union Trust Company, Executive Trustee, under Sandoz Trust No Drawing; Application May 6, 1954 Serial No't428g132 synthetic fibers in yellow shades and which are derived from monoazo dyestuffs of the formula wherein w stands for a sulfonic acid amide group which may be substituted at the nitrogen atom, R represents an 'alkyl'groupwith' 1 to-4 carbon atoms, and R stands for hydrogen or an alkyl group with 1 to 4 carbon atoms, and-wherein nucleus A may be further substituted, are known. However, the properties of these dyestuffs are not entirely satisfactory; thus for example the neutral aifinity thereof for synthetic polyamidefibers leaves something to be desired, and the shadesof the dyeings on animal and nitrogen-containingsynthetic fibers are often undesirably shifted to the red. This may be illustrated by the cobaltcontaining azo dyestuif which is obtained by'coupling diazotized 1 hydroxy 2 aminobenzene 4 sulfonic acid methylamide with-the dibutylamide of acetoacetic acid, and cobaltizing the so-obtained monoazo dyestufi. This cobalt-containing dyestufi" is but incompletely exhausted from a neutral bath onto the said fibers; the latter are dyed in orange-colored shades.

A primary object of the present invention is the embodiment of a group of cobalt-containing azo dyestuffs of the acylacetylaminoalkane serieswhich are free of the aforedescribed defects, i. e. which have an outstanding neutral aflinity for animal and nitrogen-containing synthetic fibers and which dye the latter in valuable greenish yellow shades.

This object is realized according to the present invention by the group of cobalt-containing azo dyestuffs which are prepared by coupling one mol of the diazo compound of an aminobenzene of the formula 2,82%,782 Patented Jan. 21, 1958 ice wherein x stands for OH or --OCH y stands for hy- CHrCg: SO24N a CHr-Cfiz R representing CI, CH or.-SO NI-IR", R" being H, alkyl or alkoxyalkyl, a representing a simple bond or O, alkyl being lower alkyl throughout, with (i) one mol of an acylacetylaminoalkane of the formula HO-fi HC aryl, or with (ii)' one mol of a mixture of two or more acylacetylaminoalkanes of. Formula III, and then treatin g' theresultan't monoazo dyestufl or mixture of two or more monoazo dyestuiiswith a cobalt-yielding agent.

It could not be foreseen and'is wholly unexpected that the compounds according to the present invention-for example, the cobalt complex. compounds of the monoazo dyestuffs from diazotized 1-hydroxy-2-aminobenzene4- sulfonic acid methylamide and the l-dimethyl-3-dimethylbutyl(l) amide or the 1 octylamide' of acetoacetic acidwhich are e. g. isomeric with the aforementioned" cobalt-containing' dyestuff containing the dibutyiamide of acetoacetic acid as azo component, would'possess thesur prising'property of excellent neutral drawing capacity and would yield a valuable greenish yellow shade on wool and nitrogen-containingsynthetic fibers.

The coupling of the diazo compounds with theacylacet ylaminoalkanes, according to the-invention, is preferably carried out in alkaline medium. It'is often necessary to work with emulsions or suspensions, since the acylacetylaminoalkanes are generally gels or solids, which are-not soluble in water. The obtained dyestufisare advantageously separated from the alkaline coupling masses by the addition of'hydr'o'ch'loric acid, in some. cases after preliminary decant'ation and dissolution of the reaction products in dilute'aqueous caustic soda solutions.

Valuable products are also obtained when the diazocompoundsare coupled, not with a single azo component but with a mixture of two or more azo components. The. so-obtaine'd mixtures can be subjected to metallization without prior separation thereof into the individual com ponents.

The metallization of the monazo compound or of. the. mixture 'ofmonoazo compoundsis preferably carried out. With'cobaltacetat'e, cobalt'formate or cobalt sulfate, in. aqueous suspension 'orsolution or in organic medium, for

examplein formamide or in'molten alkali metal saltof a low molecular aliphatic monocarboxylic acid. In the latter case, insoluble metal compounds-such as'cobalt hydroxide or cobalt carbonate may also be used. Metal lization-in aqueous caustic alkaline medium is particularly (in where R1 represents an' alkyl group with at least 6 and at most 18 carbon atoms, and R stands for lower alkyl or advantageous, the metal salts being added in the presence of compounds which keep cobalt dissolved in complex combination in caustic alkaline medium, e. g. tartaric acid, citric acid, lactic acid, etc. In the event that x in the formula of the aminobenzene which is used in preparing the diazo compound is -OCH the metallization is carried out under conditions which bring about a splitting of the methoxy group, e. g. by heating the monoazo dyestutf to temperatures above 100 C. in an organic medium.

Particularly valuable cobalt-containing azo dyestuffs are obtained when less than one atom of cobalt is introduced per molecule of monoazo dyestufi and, for example, so-called 1:2-complexes are prepared which correspond to the formulaman o 0-0 m-c-o-- arated from the metallization solutions generally by the.

addition of sodium chloride, followed by filtration, washing (if necessary), and drying. The products have an outstanding neutral drawing capacity and dye wool and silk from a neutral to weakly acid dyebath in valuable greenish yellow shades, which are even and full, of excellent fastness to light and of very good fastness to fulling and to washing. The new dyestuffs are also very excellently suitable for the dyeing of leather and especially of nitrogen-containing synthetic fibers, e. g. of synthetic polyamide fibers such as those sold commercially as nylon, Perlon, etc.

The following examples illustrate the invention, but are not intended to be limitative thereof. In these examples, the parts and percentages are by weight, and the temperatures are in degrees centigrade.

EXAMPLE 1 20.2 parts of' 2-amino-l-hydroxybenzenet-sulfonic acid methylamide are diazotized. The resultant diazo suspension is run, at 0-5 into a vigorously stirred emulsion of 22 parts of 1-acetoacetylamino-hexane, 40 parts of sodium carbonate, approximately 27 parts of an aqueous sodium hydroxide solution of 30% strength, and 300 parts of water. The resultant resinous monoazo dyestuii is, after decantation, dissolved in dilute aqueous sodium hydroxide solution, whereupon the solution is slowly acidified at 20 with hydrochloric acid. The precipitated dyestufl'is filtered ofi and then dried at 25-30 under reduced pressure. A brown powder is obtained which dissolves with reddish yellow coloration in dilute aqueous sodium hydroxide solution and with greenish yellow coloration in concentrated sulfuric acid.

Conversion into the cobalt complex compound is carried out as follows:

8.6 parts of the monoazo dyestufi, obtainedv according tothe first paragraph of the present example, are suspended in 100 pa ts. ofgwatent .A ,cobalt-sodium-tartrate.

: hydroxybenzene-4-sulfonic acid amideis run, at 05,

solution, consisting of 3.5 parts of crystalline cobalt sulfate, 19.3 parts of aqueous tartaric acid solution of 4.8% strength and 4.7 parts of aqueous sodium hydroxide solution of 30% strength, is stirred into the suspension at 25 The resultant cobalt complex compound precipitates; it is brought into solution by the addition of sodium hydroxide to the metallization mass. The obtained solution is stirred for one hour at 25, after which it is stirred into a saturated aqueous sodium chloride solution, and the precipitated cobalt-containing azo dyestuff filtered off and dried at 40-45 A brown-yellow powder is obtained which dissolves with yellow coloration in water and which dyes wool, silk, polyamide fibers and leather from a neutral to weakly acid bath in greenish yellow shades which are fast to light, fulling, washing and perspiration. It corresponds to the. formula EXAMPLE 2 The diazo suspension from 18.8'parts of 2-amino-1- into a well stirred suspension of 25 parts of l-acetoacetylamino-Z-butyl-butane, 40 parts of sodium carbonate, 27 parts of aqueous sodium hydroxide solution of 30% strength and 300 parts of water. the coupling, the precipitated monoazo dyestutf is filtered off and dried at 35-40". The product is a reddishyellow powder which dissolves with yellow coloration in. dilute aqueous sodium hydroxide solution and with,

greenish yellow coloration in concentrated sulfuric acid.

8.6 partsof the so-obtained monoazo dyestuff are metallized after the manner described in Example 1, with the aid of cobalt-sodium-tartrate. The obtained cobalt complex compound is soluble with yellow coloration in. water; it dyes wool, silk, synthetic polyamide fibers and leather in greenish yellow shades .which are fast to light, fulling, washing and perspiration. It corresponds to the formula:

The following table sets forth additional dyestuffs which can be prepared after the manner set forth in Example 1. These dyestuffs are characterized in the table by the respective diazo and azo components and by the shades of the dyeings of the corresponding cobalt complex compounds on wool. The identical shades are obtained on silk and on synthetic polyamide fibers.

Upon completion of A 7 pound is separated by decantation from the mother liquor. The dyestuif is then dissolved in hot dilute sodium hydroxide solution. Thersolution is freed by filtrato the formula mN-msQo I2 and possesses the same properties as the product obtainable according to Example 5.

EXAMPLE 32 100 parts of wool are entered into a bath consisting of parts of ammonium acetate and 4000 parts of Water, and the wool is digested therein for minutes at 50. Thereupon a concentrated aqueous solution of 1 part of the cobalt-containing azo dyestufi obtainable according to Example 1 is added to the bath, which is then heated to boiling in the course of 30 minutes. The bath is maintained at the boil for an additional 30 minutes, after which it is cooled and the dyed material withdrawn, rinsed with cold water and dried.

Polyamide fibers, such as nylon and Perlon, can be dyed in the same way.

The hereinbefore-mentioned cobalt compounds are Co(II) compounds.

Having thus disclosed the invention what is claimed is:

l. A cobalt-containing dye comprising the azo dye stuff which corresponds to the formula ll 00,. N

l RiHN. 0 0-0 l2 wherein n is less than 2, y is selected from the group consisting of H, CH and -NHCOCH z is selected from the group consisting of -SO alkyl, SO NH -SO NH.a1ky1, SO -NH.alkoxyalkyl,

R is: an alkyl, group with at least 6 and at mosti-18 Yearbon atoms, and R is a member selected from the group consisting of lower alkyl and aryl..

2. A cobalt-containing dye according to claim 1, wherein the azo dyestufi moieties are identical.

3. A cobalt-containing dye according to claim 1, wherein the azodyestuft moieties are different.

.4. YA cobalt-containing dye according to claim 1, wherein the azo dyestuff moieties are identical and n is one.

5. A cobalt-containing dye according to claim 1, wherein the a zodyestuff moieties are different and n is one. 6. A cobalt-containing dye "corresponding to the formula Eta-mongol 7. A cobaltcontaining dye corresponding to the formula Hm-msQo 8. cobalt-containing dye corresponding to the formula 9. A cobalt-containing dye corresponding formula 1 V HzN-OaS-Q-O i 10. A cobalt-containing dye consisting of a mixture of the cobalt-containing 'azo dyestufis corresponding to the formulae mN-ms-Qo- I Co to the and HEN-02$- N 1% I HuCu-HN-O CC 9 10 and References Cited in the file of this patent Q UNITED STATES PATENTS H:NOg 0 0C-CH! II 2,305,095 Mackenzle Dec. 15, 1942 I f-* 2,565,898 Widmer et a1. Aug. 28, 1951 I-lI---0i ---N 2,734,895 Zickendraht et a1 Feb. 14, 1956 Hz5C12HNO C-C I 

1. A COBALT-CONTAINING DYE COMPRISING THE AZO DYESTUFF WHICH CORRESPONDS TO THE FORMULA SIG-01 WHEREIN N IS LESS THAN 2, Y IS SELECTED FROM THE GROUP CONSISTING OF H, CH3 AND -NHCOCH3, Z IS SELECTED FROM THE GROUP CONSISTING OF -SO2-ALKYL, -SO2NH2, -SO2-NH.ALKYL, -SO2-NH.ALKOXYALKYL, 